Let's say I'm super crazy. (A stretch, I know.)

Let's say I mount two 500mm length steel rails 5mm from each other, and drive one positive and one negative.

Let's say I have a way to feed 1/4" ball bearing steel balls onto these rails.

Let's say it's all mounted in a slippery tube (oil nylon, or teflon) that keeps the ball on the rails if it bounces.

How many amps of current do I need to deliver, for how long, to make the ball bearing exit the rails with a speed of 200 fps? (60 m/s)

From what I can tell, I get 0.2 micronewtons times the square of the current (in amps,) and the ball weighs 1.05 grams.

v = a * t = 60

p = 0.5 = a * t * t / 2 = 60 * t / 2

t = 1 / 60

a = 1 = 2e-7 * c * c / 0.00105 = 0.000190 * c * c

c = sqrt(1/0.000190) = 72.5 Amps

That's ... not bad at all. What did I screw up in calculations? (The 0.2 micronewtons time amp squared seems the most suspect, as I couldn't get a really solid reference for that, just a mention that it's "definitionally" that way.)

(Beacuse all robots need railguns.)

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